Field of the Invention
The present invention relates to golf balls. Specifically, the present invention relates to golf balls including a core having a two-layer structure, a mid layer, and a cover.
Description of the Related Art
The greatest interest to golf players concerning golf balls is flight distance. In particular, golf players place importance on flight distances upon shots with a driver. There have been various proposals for improvement of flight performance. JP2010-188199 discloses a golf ball including a core having a high hardness at the surface thereof and a low hardness at the central point thereof. JP2013-31778 discloses a golf ball of which the hardness gradually increases from the central point of a core toward the surface of the core.
Golf players also place importance on spin performance of golf balls. When a backspin rate is high, the run is short. By using a golf ball having a high backspin rate, a golf player can cause the golf ball to stop at a target point. When a sidespin rate is high, the golf ball tends to curve. By using a golf ball having a high sidespin rate, a golf player can intentionally cause the golf ball to curve. Golf balls having excellent spin performance have excellent controllability. Advanced golf players place importance particularly on controllability upon shots with a short iron.
In rainy weather, if water is present between a clubface and a golf ball, the golf ball may slip against the clubface. Upon a shot at which a slip occurs, the spin rate is low. This phenomenon is referred to as “flyer”. The flyer can occur when lawn is present between a clubface and a golf ball. Upon a shot at which a slip occurs, a golf ball lands on a point that is farther than a point intended by a golf player. Flyer makes it difficult for golf players to predict a landing point. Golf balls with which flyer easily occurs have inferior controllability. Golf players desire golf balls with which flyer is less likely to occur. In other words, golf players desire golf balls having excellent controllability in a wet state. A golf ball having excellent controllability in a wet state is disclosed in JP2012-45223 (US2012/0052985).
Golf players' requirements for golf balls have been escalated. There is room for improvement in various performance characteristics of golf balls.
An object of the present invention is to provide a golf ball having excellent flight performance upon hitting with a driver and having excellent controllability in a wet state.